package com.pcg.yuquangong.utils;

import java.util.Calendar;
import java.util.Date;
import java.util.GregorianCalendar;

/**
 * 工具类，通过查表法实现公农历互转
 */
public class LunarUtils {

    /**
     * 支持转换的最小农历年份
     */
    private static final int MIN_YEAR = 1900;
    /**
     * 支持转换的最大农历年份
     */
    private static final int MAX_YEAR = 2099;

    /**
     * 公历每月前的天数
     */
    private static final int DAYS_BEFORE_MONTH[] = { 0, 31, 59, 90, 120, 151, 181,212, 243, 273, 304, 334, 365 };

    /**
     * 用来表示1900年到2099年间农历年份的相关信息，共24位bit的16进制表示，其中：
     * 1. 前4位表示该年闰哪个月；为0表示不润月
     * 2. 5-17位从左至右表示农历年份13个月的大小月分布，闰月紧接着月份，0表示小，1表示大；
     * 3. 最后7位表示农历年首（正月初一）对应的公历日期。 高两位表示月份，低5位表示日期
     *
     * 以2014年的数据0x955ABF为例说明：
     *                 1001 0101 0101 1010 1011 1111
     *                 闰九月                                 		 农历正月初一对应公历1月31号
     */
    private static final int LUNAR_INFO[] =
            {
                    0x84B6BF,/*1900*/
                    0x04AE53,0x0A5748,0x5526BD,0x0D2650,0x0D9544,0x46AAB9,0x056A4D,0x09AD42,0x24AEB6,0x04AE4A,/*1901-1910*/
                    0x6A4DBE,0x0A4D52,0x0D2546,0x5D52BA,0x0B544E,0x0D6A43,0x296D37,0x095B4B,0x749BC1,0x049754,/*1911-1920*/
                    0x0A4B48,0x5B25BC,0x06A550,0x06D445,0x4ADAB8,0x02B64D,0x095742,0x2497B7,0x04974A,0x664B3E,/*1921-1930*/
                    0x0D4A51,0x0EA546,0x56D4BA,0x05AD4E,0x02B644,0x393738,0x092E4B,0x7C96BF,0x0C9553,0x0D4A48,/*1931-1940*/
                    0x6DA53B,0x0B554F,0x056A45,0x4AADB9,0x025D4D,0x092D42,0x2C95B6,0x0A954A,0x7B4ABD,0x06CA51,/*1941-1950*/
                    0x0B5546,0x555ABB,0x04DA4E,0x0A5B43,0x352BB8,0x052B4C,0x8A953F,0x0E9552,0x06AA48,0x6AD53C,/*1951-1960*/
                    0x0AB54F,0x04B645,0x4A5739,0x0A574D,0x052642,0x3E9335,0x0D9549,0x75AABE,0x056A51,0x096D46,/*1961-1970*/
                    0x54AEBB,0x04AD4F,0x0A4D43,0x4D26B7,0x0D254B,0x8D52BF,0x0B5452,0x0B6A47,0x696D3C,0x095B50,/*1971-1980*/
                    0x049B45,0x4A4BB9,0x0A4B4D,0xAB25C2,0x06A554,0x06D449,0x6ADA3D,0x0AB651,0x095746,0x5497BB,/*1981-1990*/
                    0x04974F,0x064B44,0x36A537,0x0EA54A,0x86B2BF,0x05AC53,0x0AB647,0x5936BC,0x092E50,0x0C9645,/*1991-2000*/
                    0x4D4AB8,0x0D4A4C,0x0DA541,0x25AAB6,0x056A49,0x7AADBD,0x025D52,0x092D47,0x5C95BA,0x0A954E,/*2001-2010*/
                    0x0B4A43,0x4B5537,0x0AD54A,0x955ABF,0x04BA53,0x0A5B48,0x652BBC,0x052B50,0x0A9345,0x474AB9,/*2011-2020*/
                    0x06AA4C,0x0AD541,0x24DAB6,0x04B64A,0x6a573D,0x0A4E51,0x0D2646,0x5E933A,0x0D534D,0x05AA43,/*2021-2030*/
                    0x36B537,0x096D4B,0xB4AEBF,0x04AD53,0x0A4D48,0x6D25BC,0x0D254F,0x0D5244,0x5DAA38,0x0B5A4C,/*2031-2040*/
                    0x056D41,0x24ADB6,0x049B4A,0x7A4BBE,0x0A4B51,0x0AA546,0x5B52BA,0x06D24E,0x0ADA42,0x355B37,/*2041-2050*/
                    0x09374B,0x8497C1,0x049753,0x064B48,0x66A53C,0x0EA54F,0x06AA44,0x4AB638,0x0AAE4C,0x092E42,/*2051-2060*/
                    0x3C9735,0x0C9649,0x7D4ABD,0x0D4A51,0x0DA545,0x55AABA,0x056A4E,0x0A6D43,0x452EB7,0x052D4B,/*2061-2070*/
                    0x8A95BF,0x0A9553,0x0B4A47,0x6B553B,0x0AD54F,0x055A45,0x4A5D38,0x0A5B4C,0x052B42,0x3A93B6,/*2071-2080*/
                    0x069349,0x7729BD,0x06AA51,0x0AD546,0x54DABA,0x04B64E,0x0A5743,0x452738,0x0D264A,0x8E933E,/*2081-2090*/
                    0x0D5252,0x0DAA47,0x66B53B,0x056D4F,0x04AE45,0x4A4EB9,0x0A4D4C,0x0D1541,0x2D92B5          /*2091-2099*/
            };

    /**
     * 将农历日期转换为公历日期
     * @param year                        农历年份
     * @param month                        农历月，若为闰月则传入负数
     * @param monthDay                农历日
     * @return 返回农历日期对应的公历日期，year0, month1, day2.若返回null表示运行错误，请检查输入数据是否合法。
     * @param //查询区间 1900年正月初一 至 2099年腊月三十
     */
    public static int[] lunarToSolar(int year, int month, int monthDay)
    {
        int dayOffset;
        int leapMonth;
        int i;
        int pos = Math.abs(month);

        if (year < MIN_YEAR || year > MAX_YEAR || pos < 1 || pos > 12 || monthDay < 1 || monthDay > 30)
        {
            return null;
        }
        leapMonth = leapMonth(year);
        if(month<0 && pos!=leapMonth)
        {
            return null;
        }

        //0x001F为 1 1111；按位与取低5位并减1，得到当年春节的日与1的天数
        dayOffset = (LUNAR_INFO[year - MIN_YEAR] & 0x001F) - 1;
        //0x60为 01100000，按位与取得春节所对应的月份+5个0，右移5位后取得春节所对应的月份
        int basemonth = (int) ((LUNAR_INFO[year - MIN_YEAR] & 0x0060) >> 5);
        //若春节对应的月份不为1月，则需将前面几个月的天数加上
        for(int m=1;m<basemonth;m++)
        {
            dayOffset += daysInMonth(year,m);
        }
        //加上农历月份的天数差
        if(leapMonth != 0 )
        {
            if(month < 0 || month > leapMonth)
            {
                pos = pos + 1;
            }
        }
        for (i = 1; i < pos; i++)
        {
            dayOffset += daysInMyMonth(year,i);
        }
        //加上农历日的天数差
        dayOffset += monthDay;

        //阳历已跨年处理
        int yeardays = daysInYear(year);
        if (dayOffset > yeardays)
        {
            year += 1;
            dayOffset -= yeardays;
        }

        int[] solarInfo = new int[3];

        for (i = 1; i < 13; i++)
        {
            boolean isleap = isLeapYear(year);
            int iPos = DAYS_BEFORE_MONTH[i];

            if (isleap && i > 2)
            {
                iPos += 1;
            }

            if (iPos >= dayOffset)
            {
                solarInfo[1] = i;
                iPos = DAYS_BEFORE_MONTH[i - 1];
                if (isleap && i > 2)
                {
                    iPos += 1;
                }
                solarInfo[2] = dayOffset - iPos;
                break;
            }
        }
        solarInfo[0] = year;

        return solarInfo;
    }

    /**
     * 将公历日期转换为农历日期，且标识是否是闰月
     * @param year
     * @param month
     * @param monthDay
     * @return 返回公历日期对应的农历日期，year0，month1，day2，若返回月份为负数，则表示该月为闰月
     * @param //查询区间 1900-01-31 至 2100-02-08
     */
    public static int[] solarToLunar(int year, int month, int monthDay)
    {
        int[] lunarDate = new int[3];
        if(year<1900 || year > 2100 || month < 1 || month > 12 || monthDay <1 || monthDay > 31)
        {
            return null;
        }
        else if(year==1900 && month==1 && monthDay < 31)
        {
            return null;
        }
        else if(year==2100)
        {
            if(month>2)
            {
                return null;
            }
            else if(month==2 && monthDay>8)
            {
                return null;
            }
        }

        Date baseDate = new GregorianCalendar(1900, 0, 31).getTime();
        Date objDate = new GregorianCalendar(year, month - 1, monthDay).getTime();
        //与1900年春节的天数差,86400000 = 1000 * 60 * 60 * 24
        int offset = (int) ((objDate.getTime() - baseDate.getTime()) / 86400000L);

        // 用offset减去每农历年的天数计算当天是农历第几天
        // iYear最终结果是农历的年份, offset是当年的第几天
        int iYear, daysOfYear = 0;
        for (iYear = MIN_YEAR; iYear <= MAX_YEAR && offset > 0; iYear++)
        {
            daysOfYear = daysInLunarYear(iYear);
            offset -= daysOfYear;
        }
        if (offset < 0) {
            offset += daysOfYear;
            iYear--;
        }

        // 农历年份
        lunarDate[0] = iYear;

        int leapMonth = leapMonth(iYear); // 闰哪个月,1-12
        boolean isLeap = false;
        // 用当年的天数offset,逐个减去每月（农历）的天数，求出当天是本月的第几天
        int iMonth, daysOfMonth = 0;
        for (iMonth = 1; iMonth <= 13 && offset > 0; iMonth++)
        {
            daysOfMonth = daysInMyMonth(iYear, iMonth);
            offset -= daysOfMonth;
        }

        // 月份需要校正
        if (offset < 0)
        {
            offset += daysOfMonth;
            --iMonth;
        }

        // 当前月超过闰月，要校正
        if (leapMonth != 0 && iMonth > leapMonth)
        {
            --iMonth;
            if (iMonth == leapMonth)
            {
                isLeap = true;
            }
        }

        if(isLeap)
        {
            lunarDate[1] = -1 * iMonth;
        }
        else
        {
            lunarDate[1] = iMonth;
        }
        lunarDate[2] = offset + 1;

        return lunarDate;
    }

    /**
     * 将农历日期转换为公历日期
     * @param year                        农历年份
     * @param month                        农历月，若为闰月则传入负数
     * @param monthDay                农历日
     * @return 返回农历日期对应的公历日期yyyy-MM-dd格式标准字符串.若返回空串，请检查输入数据是否合法。
     * @param //查询区间 1900年正月初一 至 2099年腊月三十
     */
    public static String getTranslateSolarString(int year, int month, int monthDay)
    {
        String result = "";
        int[] soloar = lunarToSolar(year, month, monthDay);
        if(soloar!=null)
        {
            result = soloar[0] + "-";
            if(soloar[1]<10)
            {
                result = result +"0" + soloar[1];
            }
            else
            {
                result = result + soloar[1];
            }
            if(soloar[2]<10)
            {
                result = result +"-0" + soloar[2];
            }
            else
            {
                result = result +"-"+ soloar[2];
            }
        }
        return result;
    }

    /**
     * 将公历日期转换为农历日期字符串
     * @param year
     * @param month
     * @param monthDay
     * @return 返回公历日期对应的农历日期字符串，若返回为空串，则表示参数错误
     * @param //查询区间 1900-01-31 至 2100-02-08
     */
    public static String getTranslateLunarString(int year, int month, int monthDay)
    {
        String result = "";
        int[] lunar = solarToLunar(year, month, monthDay);
        if(lunar!=null)
        {
            String tp = getLunarMonthName(lunar[1]);
            result = lunar[0]+"年"+tp+"月";
            tp = getLunarDayName(lunar[2]);
            result = result + tp;
        }
        return result;
    }

    /**
     * 根据阳历的年月日获取字符串
     * @param year 年
     * @param month 月
     * @param monthDay 日
     * @return
     */
    public static String getSolarString(int year, int month, int monthDay)
    {
        String result = "";
        if(year>0)
        {
            result = year + "-";
        }
        if(month<10)
        {
            result = result +"0" + month;
        }
        else
        {
            result = result + month;
        }
        if(monthDay<10)
        {
            result = result +"-0" + monthDay;
        }
        else
        {
            result = result +"-"+ monthDay;
        }
        return result;
    }

    /**
     * 根据农历的年月日获取字符串
     * @param year 年
     * @param month 月
     * @param monthDay 日
     * @return
     */
    public static String getLunarString(int year, int month, int monthDay)
    {
        String result = "";
        if(year>0)
        {
            result = year + "年";
        }
        String tp = getLunarMonthName(month);
        result += tp+"月";
        tp = getLunarDayName(monthDay);
        result += tp;
        return result;
    }

    /**
     * 获取阳历日期是星期几
     */
    public static int getWeekByDateStr(int year,int month,int day)
    {
        int x = -1;
        try
        {
            Calendar cal = Calendar.getInstance();
            cal.set(year, month, day);
            x = (cal.get(Calendar.DAY_OF_WEEK) + 6) % 7;
            if(x==0)
            {
                x = 7;
            }
        }catch(Exception e) {}

        return x;
    }

    /**
     * 判断阳历year年是否为闰年
     *
     * @param year 将要计算的年份
     * @return 返回传入年份的总天数
     */
    public static boolean isLeapYear(int year)
    {
        if(year % 4 !=0)
        {
            return false;
        }
        else if(year % 100 == 0)
        {
            if(year % 400 ==0)
            {
                return true;
            }
            else
            {
                return false;
            }
        }
        else
        {
            return true;
        }
    }

    /**
     * 传回阳历 year年的总天数
     *
     * @param year 将要计算的年份
     * @return 返回传入年份的总天数
     */
    public static int daysInYear(int year)
    {
        return isLeapYear(year) ? 366 : 365;
    }
    /**
     * 传回阳历 year年month月的总天数
     *
     * @param year 将要计算的年份  month 要传入的月份
     * @return 返回传入年份的总天数
     */
    public static int daysInMonth(int year,int month)
    {
        if(month!=2)
        {
            if(month <= 7)
            {
                if(month % 2 == 1)
                {
                    return 31;
                }
                else
                {
                    return 30;
                }
            }
            else
            {
                if(month % 2 == 1)
                {
                    return 30;
                }
                else
                {
                    return 31;
                }
            }
        }
        else
        {
            if(year>0 && isLeapYear(year))
            {
                return 29;
            }
            else
            {
                return 28;
            }
        }
    }
    /**
     * 传回农历 year年的总天数
     *
     * @param year 将要计算的年份
     * @return 返回传入年份的总天数，若返回-1则表示运行错误，请检查传入参数
     */
    public static int daysInLunarYear(int year)
    {
        if(year < 1900 || year >2099)
        {
            return -1;
        }
        int i=0;
        int sum = 348;
        //若不闫月，且所有月都是小月，农历一年348天；若闫且所有月都是小月，则为377天
        if (leapMonth(year) != 0)
        {
            sum = 377;
        }
        //0x0FFF80为1111 1111 1111 1000 0000，取当年各个月份的大小，每有一个大月加一天
        int monthInfo = LUNAR_INFO[year - MIN_YEAR] & 0x0FFF80;
        //0x80000为  1000 0000 0000 0000 0000，0x40为100 0000
        for (i = 0x80000; i > 0x40; i >>= 1)
        {
            if ((monthInfo & i) != 0)
                sum += 1;
        }
        return sum;
    }

    /**
     * 传回农历 year年闰哪个月 1-12 , 没闰传回 0
     *
     * @param year 将要计算的年份
     * @return 传回农历 year年闰哪个月1-12, 没闰传回 0.若传回－1则表示传入参数错误
     */
    public static int leapMonth(int year)
    {
        if(year < 1900 || year > 2099)
        {
            return -1;
        }
        return (int) ((LUNAR_INFO[year - MIN_YEAR] & 0xF00000)) >> 20;
    }

    /**
     * 传回农历 year年month月的总天数,错误返回-1
     * 若要查询闰月的天数，请将此月份设为负数
     */
    public static int daysInLunarMonth(int year, int month)
    {
        int pos = Math.abs(month);
        if(year<1900 || year > 2099 || pos > 12 || pos == 0)
        {
            return -1;
        }
        int leap = leapMonth(year);
        if(month < 0 && pos != leap)
        {
            return -1;
        }

        if(leap != 0 )
        {
            if(month < 0 || month > leap)
            {
                pos = pos + 1;
            }
        }

        if ((LUNAR_INFO[year - MIN_YEAR] & (0x100000 >> pos)) == 0)
            return 29;
        else
            return 30;
    }

    /**
     * 传回农历 year年的月份列表，闰月以负数表示
     * 若要查询通用年份的月份列表，则将年份设为负数
     * @return 以int数组的形式返回月份列表，若返回null表示参数错误
     */
    public static int[] getLunarMonths(int year)
    {
        if((year>0 && year<1900) || year >2099)
        {
            return null;
        }
        int[] months;
        int leap = 0;
        if(year >0)
        {
          leap = leapMonth(year);
        }
        if(leap == 0)
        {
            months = new int[12];
            for(int i=0;i<12;i++)
            {
                months[i] = i+1;
            }
        }
        else
        {
            months = new int[13];
            for(int i=0;i<13;i++)
            {
                if(i+1<=leap)
                {
                    months[i] = i+1;
                }
                else if(i==leap)
                {
                    months[i] = -1 * leap;
                }
                else
                {
                    months[i] = i;
                }
            }
        }
        return months;
    }

    /**
     * 根据农历的数字月份获取农历月份的字符串形式
     * @return 若返回null表示参数错误
     */
    public static String getLunarMonthName(int month)
    {
        String res = "";
        String[] months = {"正","二","三","四","五","六","七","八","九","十","冬","腊"};
        int x = Math.abs(month);
        if(month<0)
        {
            res = "闰";
        }
        res += months[x-1];
        return res;
    }

    /**
     * 根据农历的数字月份获取农历月份的字符串形式
     * @return 若返回null表示参数错误
     */
    public static String getLunarDayName(int day)
    {
        String res = "";
        String[] days1 = {"初","十","廿", "三"};
        String[] days2 = {"十","一", "二", "三", "四", "五", "六", "七", "八", "九"};
        int x = (int) day / 10 ;
        int y = day % 10;
        if(x == 1 && y == 0)
        {
            res = "初十";
        }
        else
        {
            res = days1[x] + days2[y];
        }
        return res;
    }

    /**
     * 传回农历 year年pos月的总天数，总共有13个月包括闰月
     * 月份为按13个月的位置
     */
    private static int daysInMyMonth(int year, int pos)
    {
        if ((LUNAR_INFO[year - MIN_YEAR] & (0x100000 >> pos)) == 0)
            return 29;
        else
            return 30;
    }

}